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Fair Value Measurements (Narrative) (Details) $ in Thousands, gal in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025 USD ($) Swap € / shares $ / gal	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) Swap € / shares $ / gal gal	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Derivatives Fair Value [Line Items]
Debt instrument, face amount	$ 325,000		$ 325,000
Fair Value, Inputs, Level 1 [Member]
Derivatives Fair Value [Line Items]
Fair value of debt	314,900		$ 314,900
Fuel Hedge Contracts [Member]
Derivatives Fair Value [Line Items]
Derivative underlying hedge percent			80.00%
Derivative, nonmonetary notional amount, volume | gal			17.4
Reclassification of derivative gain (losses) to earnings net of tax	$ 192	$ (644)	$ (450)	$ (882)
Fair value hedge liabilities					$ 1,100
Fuel Hedge Contracts [Member] | Minimum [Member]
Derivatives Fair Value [Line Items]
Fixed price range | $ / gal	2.03		2.03
Fuel Hedge Contracts [Member] | Maximum [Member]
Derivatives Fair Value [Line Items]
Fixed price range | $ / gal	2.55		2.55
Foreign Currency Exchange Hedge Contracts [Member]
Derivatives Fair Value [Line Items]
Reclassification of derivative gain (losses) to earnings net of tax				(42)
Reclassification of derivative (gains) losses to earnings net of cash settlements and taxes				42
Foreign Currency Exchange Hedge Contracts [Member] | Minimum [Member]
Derivatives Fair Value [Line Items]
Fixed price range | € / shares	1.01		1.01
Foreign Currency Exchange Hedge Contracts [Member] | Maximum [Member]
Derivatives Fair Value [Line Items]
Fixed price range | € / shares	1.13		1.13
Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Reclassification of derivative gain (losses) to earnings net of tax	$ 64	$ 112	$ 196	$ 112
Derivative notional amount	75,000		75,000
Fair value hedge liabilities	$ 161		$ 161
Derivative, maturity date			Aug. 24, 2026
Floating-rate debt to weighted average fixed interest rate	11.62%		11.62%
Derivative, average fixed interest rate	3.87%		3.87%
Number of interest rate swaps | Swap	2		2

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